Definition: disruption of the squamous epithelium. The desmosomal connections between the epithelial cells are destroyed. As a result the cells separate and become round.
References
Dhitavat J, Fairclough RJ, Hovnanian A, Burge SM. Calcium pumps and keratinocytes: lessons from Darier’s disease and Hailey-Hailey disease. Br J Dermatol. 2004 May;150(5):821-8. PMID: 15149492